private bool HandleCollision(Entity e, CollidableComponent collidable, CollidableComponent other)
{
long playerLayer = this.layerManager.GetBit("Player");
long asteroidLayer = this.layerManager.GetBit("Asteroid");
long projectileLayer = this.layerManager.GetBit("Projectile");
long borderLayer = this.layerManager.GetBit("Border");
if (collidable.CollisionLayer.HasLayer(playerLayer) && other.CollisionLayer.HasLayer(asteroidLayer))
{
return(this.CheckAgeAndRespawn(e));
}
else if (collidable.CollisionLayer.HasLayer(projectileLayer) && other.CollisionLayer.HasLayer(asteroidLayer))
{
//this.ParticleEngine?.SpawnParticles(10, collidable.Collision.CollisionPoint, Color.White);
return(this.AddScoreAndDestroy(e));
}
else if (collidable.CollisionLayer.HasLayer(asteroidLayer) && other.CollisionLayer.HasLayer(projectileLayer))
{
return(this.SplitAndOrDestroy(e));
}
else if (collidable.CollisionLayer.HasLayer(asteroidLayer) && other.CollisionLayer.HasLayer(borderLayer))
{
return(this.RepellFromBorderInward(e, 100));
}
else if (collidable.CollisionLayer.HasLayer(playerLayer) && other.CollisionLayer.HasLayer(borderLayer))
{
return(this.StopAtBorder(e, collidable, other));
}
return(true);
}
public override void Update(float elapsedSeconds)
{
foreach (Entity e in this.actives.Values)
{
CollidableComponent collidable = e.GetComponent <CollidableComponent>();
System.Diagnostics.Debug.Assert(collidable != null, "CollidableComponent not found");
for (int i = 0; i < collidable.Collisions.Count; i++)
{
this.HandleCollision(e, collidable, collidable.Collisions[i]);
}
collidable.Collisions.Clear();
}
}
private bool StopAtBorder(Entity e, CollidableComponent collidable, CollidableComponent other)
{
TransformComponent transform = e.GetComponent <TransformComponent>();
MotionComponent motion = e.GetComponent <MotionComponent>();
Vector2 penetrationVector = collidable.Collider.PenetrationVector(other.Collider);
if (!(penetrationVector == Vector2.Zero))
{
transform.Position -= penetrationVector;
Vector2 offsetDirection = Vector2.Normalize(penetrationVector);
Vector2 offsetMagnitude = new Vector2(Math.Abs(motion.Velocity.X), Math.Abs(motion.Velocity.Y));
motion.Velocity -= offsetDirection * offsetMagnitude;
}
return(true);
}
/// <summary>
/// Checks all entites in the given list whether or not they intersect with each other
/// </summary>
/// <param name="entities">The list of entities</param>
private void CheckCollisions(IReadOnlyList <Entity> entities)
{
for (int i = 0; i < entities.Count - 1; i++)
{
CollidableComponent collidable1 = entities[i].GetComponent <CollidableComponent>();
TransformComponent transform1 = entities[i].GetComponent <TransformComponent>();
System.Diagnostics.Debug.Assert(collidable1 != null, "CollidableComponent not found");
System.Diagnostics.Debug.Assert(transform1 != null, "TransformComponent not found");
//collidable1.Collider.ApplyTransform(transform1.Position, transform1.Rotation, transform1.Scale);
Rectangle boundingRectangle1 = collidable1.Collider.GetBounds();
for (int j = i + 1; j < entities.Count; j++)
{
CollidableComponent collidable2 = entities[j].GetComponent <CollidableComponent>();
TransformComponent transform2 = entities[j].GetComponent <TransformComponent>();
System.Diagnostics.Debug.Assert(collidable2 != null, "CollidableComponent not found");
System.Diagnostics.Debug.Assert(transform2 != null, "TransformComponent not found");
// check if collision layers match
if (collidable1.CollisionLayer.Matches(collidable2.CollisionMask) || collidable2.CollisionLayer.Matches(collidable1.CollisionMask))
{
ulong keyPair = this.GetPairedKey(entities[i].EntityId, entities[j].EntityId);
// note: the following is necessary if spatial grid is being used
if (this.checkedPairs.Add(keyPair)) // check if this pair has already been processed
{
//collidable2.Collider.ApplyTransform(transform2.Position, transform2.Rotation, transform2.Scale);
Rectangle boundingRectangle2 = collidable2.Collider.GetBounds();
if (boundingRectangle1.Intersects(boundingRectangle2)) //broadphase, check if objects MAY collide
{
if (collidable1.Collider.Intersects(collidable2.Collider)) //narrowphase, (add missing colliders (line))
{
collidable1.Collisions.Add(collidable2);
collidable2.Collisions.Add(collidable1);
}
}
}
}
}
}
}
private void SpatialHashing()
{
this.spatialGrid.Initialize();
// populate grid and apply transform to colliders
for (int i = 0; i < this.targets.Count; i++)
{
CollidableComponent collidable = this.targets[i].GetComponent <CollidableComponent>();
TransformComponent transform = this.targets[i].GetComponent <TransformComponent>();
System.Diagnostics.Debug.Assert(collidable != null, "CollidableComponent not found");
System.Diagnostics.Debug.Assert(transform != null, "TransformComponent not found");
collidable.Collider.ApplyTransform(transform.Position, transform.Rotation, transform.Scale);
this.spatialGrid.Add(collidable.Collider.GetBounds(), this.targets[i]);
}
//Parallel.For(0, this.spatialGrid.Length, c =>
//{
//WIP: still no unique collision check (also, perf. benefit?)
//desc: loop over entities vs loop over cells
////for (int i = 0; i < this.targets.Count; i++)
////{
//// CollidableComponent collidable = this.targets[i].GetComponent<CollidableComponent>();
//// IndexedList<Entity> entities = this.spatialGrid.GetUniqueCellContents(collidable.Collider.GetBounds());
//// this.CheckCollision(this.targets[i], entities);
//// //this.CheckCollisions(entities);
////}
for (int i = 0; i < this.spatialGrid.CellCount(); i++)
{
this.CheckCollisions(this.spatialGrid.GetCellContent(i));
}
//});
}
public void Draw(float elapsedSeconds, SpriteBatch spriteBatch)
{
if (this.isDebug)
{
if (this.UseSpatialHashing)
{
//note: test only
Kadro.Physics.PhysicsVisualizer.DrawSpatialGridCells(spriteBatch, this.spatialGrid.GetCells());
//todo: move this to another class (maybe even spatialgrid)
//for (int i = 0; i < GameConfig.NumCells.X; i++)
//{
// spriteBatch.DrawLineSegment(new Vector2(i * GameConfig.CellSize.X, 0), new Vector2(i * GameConfig.CellSize.X, GameConfig.WorldSize.Y), Color.Blue, 1);
//}
//for (int i = 0; i < GameConfig.NumCells.Y; i++)
//{
// spriteBatch.DrawLineSegment(new Vector2(0, i * GameConfig.CellSize.Y), new Vector2(GameConfig.WorldSize.X, i * GameConfig.CellSize.Y), Color.Blue, 1);
//}
}
for (int i = 0; i < this.targets.Count; i++)
{
CollidableComponent collidable = this.targets[i].GetComponent <CollidableComponent>();
TransformComponent transform = this.targets[i].GetComponent <TransformComponent>();
System.Diagnostics.Debug.Assert(collidable != null, "CollidableComponent not found");
System.Diagnostics.Debug.Assert(transform != null, "TransformComponent not found");
collidable.Collider.ApplyTransform(transform.Position, transform.Rotation, transform.Scale);
collidable.DebugDraw(spriteBatch, 1);
spriteBatch.DrawLineSegment(transform.Position, transform.EntityToWorld(VectorExtensions.AngleToVector2(0f) * 20), Color.Green, 1);
spriteBatch.DrawLineSegment(transform.Position, transform.Position + Vector2.One, Color.Brown, 1);
//collidable.Collider.GetBounds().Draw(spriteBatch, Color.Violet, 1);
}
}
}
public virtual void OnCollisionExit(CollidableComponent other)
{
}
